Store global console history in plugin.getStateLocation()/history.py

Includes pulling out global history code into new class and some
additional tests.
Merge branch 'save_interactive_console_commands_to_persistent_history' into opengdatrunk
Fix interaction with XML-RPC.

PyDev relied on a hard coded string, the recent commit that upgraded
(91db3ab) xmlrpc-* changed this string.
Add script_inputs and script_outputs to builtins. This is to support PythonPydevScript workflow actor.
Change python discovery to default to including all paths found
in sys.path and to use the user supplied path to python in preference
to sys.executable
Merge branch 'fix_xmlrpc_upgrade' into opengdatrunk
Merge branch 'proposed_pydev_changes' into opengdatrunk